The invention relates to a linear drive comprising a housing, a housing cover arranged on at least one terminal region, position detecting means arranged in the housing and an electromechanical connection means placed at the laterally aligned outer face of the housing cover, said connection means serving for the detachable connection of an electrical conductor arrangement leading from the outside to the linear drive from the side.
Fluid operated linear drives as a rule comprise an elongated housing having housing covers arranged at the ends and a piston accommodated in the housing, said piston being able to be caused to perform a linear movement by being acted upon by fluid. The linear motion may be transmitted and employed to drive some other instrumentality using a force transmitting dog. In order to detect one or more positions of the piston the linear drive is fitted with position detecting means, which by way of an electrical conductor arrangement, normally in the form of a cable, can be connected with an external electronic evaluating means.
In the case of a linear drive as disclosed in the German patent publication (utility model) 20,014,353.0 the position detecting means are accommodated in the wall of the housing of the linear drive. The making of electrical contact takes place from the side of the linear drive at a housing cover, from which there extends a connection unit with position detecting means.
One object of the present invention is to provide a linear drive which has even more compact dimensions and is extremely simple to clean.
In order to achieve these and/or other objects appearing from the present specification, claims and drawings, in the present invention the electromechanical connection means is accommodated in a completely sunk manner in the housing cover without standing proud of the laterally aligned outer face.
While in the case of the prior art electromechanical connection means stands proud to the side past the housing cover in the invention it is now completely sunk into the housing cover. The transverse dimensions of the linear drive are hence substantially reduced. Furthermore, cleaning becomes a substantially simpler task so that the linear drive is well suited for applications in the foodstuff industry.
Further advantageous developments of the invention are defined in the claims.
The electromechanical connection means is preferably provided with plug contact elements for making electrical contact of a connection part connected with the electrical conductor arrangement. The plug contact elements are preferably designed in the form of plug pins, the connection part to be connected being in the form of a jack.
The parts serving for mechanically securing a connection part connected with the electrical conductor arrangement, of the electromechanical connection means preferably comprise a screw thread, particularly convenient design having a female screw thread. The latter may be integrated in the housing cover in a particularly simple fashion. Furthermore, thread sizes under M8 may be simply employed in a relatively simple manner.
In principle it would be possible for the electromechanical connection means to be mounted in the housing cover so as to be sunk in relation to the lateral outer face of the housing cover. More particularly for reasons of ease of cleaning it is however to be recommended to provide for installation so as to be flush with the lateral outer face of the housing cover.
The position detecting means may for instance be constituted by a position sensor. A design using a displacement measuring system would however also be possible.
Preferably the linear drive is in the form of a fluid operated one, a piston able to be driven by fluid force being arranged in the housing. The piston is provided with actuating means, which are capable of operating the position detecting means without making physical contact.
Further advantageous developments and convenient forms of the invention will be understood from the following detailed descriptive disclosure of one embodiment thereof in conjunction with the accompanying drawings.